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Could someone help me with these math problems? I can't figure them out. Solve the linear equation;
x+2y=15
y=-2x+0 9x-12y=-3
-12x+16y=4? Make a conjecture about the next item in the sequence.1, -4, 9, -16,? 15.00g of Si reacts with 25.00g of F2 to produce 28.67g of SiF4. Which reactant is the limiting reagent? Problem involving math induction! If m and n are distinct real numbers, prove that (m+2)^2 = (n+2)^2 if and only if x+y=-4? Find the complement of the angle 3pi/7. Please show steps!?